This invention relates to a publicity board with rotating prismatic members. In particular, the invention relates to a publicity board of the type comprising a plurality of side-by-side prismatic members, each of which possesses display faces for carrying respective portions of publicity images, and further comprising motion generator means arranged to rotate the prismatic members in such a manner as to cyclically cause the faces of each prismatic member to lie in a single display plane in order to wholly compose the respective publicity image. Publicity boards of the aforesaid type are particularly convenient in that they enable generally three publicity images to be presented in sequence in the same space, thus enabling the number of publicity messages directed towards the user to be tripled.
One of the drawbacks of publicity boards of the aforesaid type is the excessive complexity of the transmission systems used for transmitting motion from the motion generator means to the various prismatic members. In this respect, said motion transmission means are constituted by chains or belts, or alternatively worms and associated helical gears, which are of particularly high cost and require periodic maintenance.